International March of the Living—an annual educational program that brings students from all over world to Poland in order for them to study the history of the Holocaust—arranged the trip for Kanter, who is Jewish.

On the evening of March 25, following Kanter’s visit to the camps, Kanter joined teen heartthrob and pop star Bieber onstage for a concert in Poland.

This was not the first time that Kanter, who became Bieber’s guitarist after performing with him on a popular Canadian TV show in 2009, has demonstrated his Jewish identity while working for Bieber. In April 2011, Kanter performed a Jimi Hendrix-style rendition of Hatikvah before Bieber stepped onstage to perform at Tel Aviv’s Hayarkon Park. And “Justin Beiber’s Musical Father Figure, Dan Kanter,” a 2011 story in the Journal, describes how Kanter is the reason that Bieber, a devout Christian, says the “The Shema” before every concert.